BIG BANG coming from the out drive

[JimmyDubai]

Hi, can you give me your opinion please: I own a Searay Sundance 290 from 1996 and a Bravo II drive. I was cruising at 3000 RPM, all good and as soon as I started to slow down, a massive BANG was heard and the throttle lever got stuck . In idle I tried to engage forward or reverse to no avail. What could happen? I had to be rescued and brought back to the marina (10 people on board).


REPLY

 

[Soulshine]

Yikes.

Can you move the shifter in and out of gear with the engine off?

Is the boat out of the water yet?

 

[JimmyDubai]

Continuing with the story..... 24 hours earlier I wanted to lubricate the cables that control throttle and gear change and I had my wife moving the throttle lever back and forth several times while I was spraying WD-40 in the cables (engine off). Then we went for a ride, no issues, this morning no issues leaving the marine for our ride, but it was only until I started to slow down to reach the destination when this thing happened. ..... What do you think?

 

[JimmyDubai]

Yikes.

Can you move the shifter in and out of gear with the engine off?

Is the boat out of the water yet?

No, I can't. The shifter is stuck. The boat is still in the water

 

[Bt Doctur]

Bravo drives are usually never shifted when not running.
Do you have a res bottle and is there oil in it.
If no res bottle when was the drive serviced and oil changed last.
If low/no oil then suspect a siezed bearing causing a broken shaft

 

[Creekwood]

Why did you lubricate the shift/throttle cables to begin with? Was there something going on before that was giving you trouble?

 

[Strecker25]

When that happened on our alpha the lower had given out by way of the clutch imploding, we were also at 3500 and it sheared the vertical driveshaft off where it enters the upper housing. Bravos are way beefier, so I doubt that exact thing happened but maybe you locked the lower or upper up. Can you turn the prop by hand while floating in the slip?

 

[scoflaw]

massive bang = need a very expensive rebuild or need another drive. Not that you needed to hear that.

 

[Soulshine]

Good point about turning the prop.

Tilt the drive up and see if you can turn it from the swim platform when in neutral.

Either way, it doesn’t bode well.

 

[blaster]

A complete Bravo two will set you back a little over $6000 in the USA. Not sure about shipping one to UAE and duty. Hopefully the whole thing didn't blow up.

Found a remanufactured one on eBay for less with a $1000 core charge.
https://m.ebay.com/itm/REMANED-MERC...m=282824798695&_trksid=p2385738.c100694.m4598

 

[Brite Idea]

A friend of mine had it happen and it was some kind of shifter failure in the drive. It happened to him while he was docking and he hit another boat all while he was trying to move the shifter but it was frozen solid. I hope yours isn't too bad of a problem.

 

[Thornton69]

Almost sounds like an impact with something. Does the engine still turn over and if so, any noise while it is running?

 

[JimmyDubai]

Bravo drives are usually never shifted when not running.
Do you have a res bottle and is there oil in it.
If no res bottle when was the drive serviced and oil changed last.
If low/no oil then suspect a siezed bearing causing a broken shaft

Res is at proper level and drive oil was replaced just 20 hours ago.

 

[JimmyDubai]

Why did you lubricate the shift/throttle cables to begin with? Was there something going on before that was giving you trouble?

Good point. When the engine is cold, idle shows 750/800 RPM but after a ride and a hot engine, it climbs up to 1,300 RPM so it is very annoying to dock the boat in those conditions so I thought it might be the cable system in need of some lubrication. I never had the chance to see if it worked or not and I am not sure if this is the reason for the big BANG

 

[JimmyDubai]

When that happened on our alpha the lower had given out by way of the clutch imploding, we were also at 3500 and it sheared the vertical driveshaft off where it enters the upper housing. Bravos are way beefier, so I doubt that exact thing happened but maybe you locked the lower or upper up. Can you turn the prop by hand while floating in the slip?

Correct, I can spin the propeller free

 

[JimmyDubai]

Good point about turning the prop.

Tilt the drive up and see if you can turn it from the swim platform when in neutral.

Either way, it doesn’t bode well.

Yes, that is what I did, and it turns freely

 

[JimmyDubai]

A friend of mine had it happen and it was some kind of shifter failure in the drive. It happened to him while he was docking and he hit another boat all while he was trying to move the shifter but it was frozen solid. I hope yours isn't too bad of a problem.

Hit another boat??? Well, that reminds me of something..... few months ago, the shifter cable got stuck in the flywheel in reverse position and I hit another boat.... lesson learnt? I should have switched the engine off immediately and act quickly by way of fenders in the impact zone if you know what I mean...... As someone already said: drives...never again.

 

[JimmyDubai]

Almost sounds like an impact with something. Does the engine still turn over and if so, any noise while it is running?

Great point too: the engine runs good, no noise

 

[Soulshine]

Hmm, I’m making a direct attribution, but shifting a lot while docking at 1300 RPM wasn’t the best thing for the drive in general.

I’ve never owned a bravo, but an Alpha would whack into gear at that speed.

My last boat had twin OMC Cobras and at anything over 800 you couldn’t shift with both hands and a helper.

No more out drives for me either.

 

[Lazy Daze]

Obviously I'm just taking a stab at this since it's hard to accurately diagnose things over the net, and regardless the drive needs to come off and the actual issue will be found. But, in the meantime...

-- If you hit something hard enough to damage a Bravo drive, you most likely would have felt the impact. And 100% guaranteed that there would be physical damage to the exterior casing. Since that would have been very noticeable and you didn't mention that...

-- When you did the shifting into and out of gear with the engine off, damage was done to the shifting mechanism in the drive. This is almost guaranteed to happen when a Bravo drive is shifted without the engine running. An Alpha can be shifted with no issues.

-- You left the marina and were still able to get into gear at this point. Running up on plane vibrated things a little more and the final damage was done. As long as you kept the throttle on, the drive stayed engaged in gear. Once you let off the throttle it allowed the drive to shift out of gear (since the shifting mechanism was now damaged to the point of failure).

-- At this point, the drive slipped out of gear at a high RPM and because of the pressure of the water on the prop started turning backwards. The gears then (because they weren't being controlled by a cable anymore) tried to shift into fwd or reverse at the same time the prop was spinning very fast.

-- Essentially, the drive tried to shift into gear with the prop spinning very fast. Like reving your engine up in neutral and quickly popping the tranny into gear.